DMD range support?

[Steven Schveighoffer]

"Sergey Gromov" wrote
> Sat, 10 Jan 2009 13:53:44 -0500, Jarrett Billingsley wrote:
>
>> On Sat, Jan 10, 2009 at 12:36 PM, Sergey Gromov <snake.scaly at gmail.com> 
>> wrote:
>>> DMD supports ranges in foreach for more than a month, but I still cannot
>>> find any docs or at least examples of the range syntax.  Lots of
>>> syntaxes were discussed and it's absolutely not obvious which of them
>>> actually got into the compiler.
>>>
>>> Is this page still relevant?
>>> http://ssli.ee.washington.edu/~aalexand/d/tmp/std_range.html
>>>
>>
>> Maybe it just means the ranges in std.range got an opApply, or some
>> kind of special treatment by the compiler?
>
> No, the following works:
>
> struct Generator(int start, int step, int end)
> {
>  private int head_ = start;
>  int head() { return head_; }
>  void next() { head_ += step; }
>  bool empty() { return head_ > end; }
> }
>
> import std.stdio;
>
> void main()
> {
>  Generator!(2, 7, 50) gen;
>  foreach (i; gen)
>    writefln(i);
> }

I'd really like to know the code generation -- A delegate probably isn't 
generated anymore?  I agree more documentation is sorely needed in the spec.